2007 Ford Explorer xlt 4.6 V8 codes P0300 P0303 P0304 P0300 P0303 P0304

[Sport Trac Mike L]

I recently bought this 2007 Explorer 4.6 V8 from a dealer wit 148k miles on the odometer. It ran like a champ despite the fact that it had common problem with the passenger side exhaust manifold studs that tend to break. When I turn the car on you would hear the ticking until after about 10 or 20 seconds (Little longer during cold weather) then would idle quietly as if the car was off. Still ran like a champ. 3 days ago we got 1ft of snow and as I start the car it starts but shaking during idle and poor gas milage which it never did before. As I drive it would sputter and as I drive it would be very hesitant Then CEL came on then at times it would blink. I pulled the codes and it came up with 2 codes for cylinder#4 and a heater circuit bank#2 . Took the car to my local shop called Technology R inc the famed shop NYC that built the infamous white GTR which won a 50k street race a few weeks back and went viral all over YouTube and instagram and a bunch of other high performance street and show cars that came out of this shop. They changed the oil + oil filter, they supposedly changed spark plugs and an o2 sensor and warned me that the exhaust manifold leak could of triggered the o2 sensor to go blank. So I pay $450 for a ****ing tune up thinking the issue is rsolved and Ima drive out their shop as if it was brand new. And as I drive off the car was still shaking and still hesitant apon throttle then the CEL comes back on. This time it only had 1 code for cylinder#4 misfire so I bought a new coil for Cylinder#4 which I replaced myself. Pulled the codes after and still says cylinder#4 misfire So I decided to take my Explorer back to Technology R where they told me cylinder#4 injector was dead. They replaced it... So I drive off and the same shaking and hesitations persist then boom...... CEL comes on. Pulled the code again and these codes came up P0300, P0303, P0304, P0300, P0303, P0304.... Now..... I've always looked up to these guys as the kid coming outta Brooklyn Because being a fellow street Racer myself. If it was Honda Day or any type of show car event Technology R came out swinging. If It was a street race Technology R was always known to have the streets most powerful cars (1,000 HP bolt on gtr, and a bunch of other powerful daily driven cars). My thing is I wanna know what is my exact problem and what do I need to get my 4.6 back to normal no shaking or none of that stuff. PLEASE HELP. I HAVE REALLY GOOD FAITH IN THESE GUYS. TELL ME WHAT PARTS I WILL NEED TO GET HER BACK TO NORMAL. THANK U

 

[Explorer_PL]

Do you know if and how many spark plugs they changed ? Very few shops want to do that job since they break in the heads and then you need special tools to remove the broken parts.
Your symptoms are typical of old plugs that have never been changed or need replacement again.
You would be better off finding a shop that specializes in Mustangs since they used same engines in those years. Also, if you used some aftermarket coils, that may be a problem as well. Those Ford triton engines are very sensitive when it comes to the initiation parts.
And lastly, check the wires leading to the coils and injectors for any wear. You may be replacing parts all day long and maybe there is a broken wire or something.

 

[Sport Trac Mike L]

They are stock coils. I was gonna try aftermarket coils until I read this lol. Are the auto zone brand good?

 

[Explorer_PL]

Mike -
Autozone are "no brand" coils. Get genuine Motorcraft ones from Amazon. They are pricier but unless the coil has a Ford part # stamped on it, I would not bother. Can you check the paperwork which plugs they changed ?
Also, before you do that, swap the coils between the cylinders and see if the error moves from 303 and 304 to another 30x.
If i does then it's the coil, if not then most likely the sparkplug.

PS: No need for "f" words

 

[Sport Trac Mike L]

Spark plugs and coils are brand new. Any where else to look?

 

[Explorer_PL]

Looks like you have your own scanner - good.
Looks like the problem is on cylinders # 3 and 4 which are passenger side 3rd and 4th counting from the grill.
If they misfire a lot, they will trigger "multiple misfire" 300.

I would move the coils and the sparkplugs from 3 and 4 to 1 and 2 (You could do just coils but since you have them out get the plugs as well).

Now, since the shop replaced all the sparkplugs, you should not have any problems taking them out (9/16 deep well sparkplug socket with extention).

https://www.amazon.com/OTC-6900-F-150-Spark-Socket/dp/B000NBVFN2


Drive the car and see if the errors changed to 301 and 302, if they did, then swap the coils back, and test it again, if the errors moved back to 303 and 304 then the coils are bad.
It's not unusual for new parts to be bad right out of package.
If nothing changed, then try swapping the injectors same way.
Inspect the little wires feeding the coils and injectors.
If that gets you nowhere, next step would be compression test.

For now, those are all my recommendations.

Maybe someone else will chime in.

 

[Sport Trac Mike L]

Looks like you have your own scanner - good.
Looks like the problem is on cylinders # 3 and 4 which are passenger side 3rd and 4th counting from the grill.
If they misfire a lot, they will trigger "multiple misfire" 300.

I would move the coils and the sparkplugs from 3 and 4 to 1 and 2 (You could do just coils but since you have them out get the plugs as well).

Now, since the shop replaced all the sparkplugs, you should not have any problems taking them out (9/16 deep well sparkplug socket with extention).

https://www.amazon.com/OTC-6900-F-150-Spark-Socket/dp/B000NBVFN2


Drive the car and see if the errors changed to 301 and 302, if they did, then swap the coils back, and test it again, if the errors moved back to 303 and 304 then the coils are bad.
It's not unusual for new parts to be bad right out of package.
If nothing changed, then try swapping the injectors same way.
Inspect the little wires feeding the coils and injectors.
If that gets you nowhere, next step would be compression test.

For now, those are all my recommendations.

Maybe someone else will chime in.

Looks like you have your own scanner - good.
Looks like the problem is on cylinders # 3 and 4 which are passenger side 3rd and 4th counting from the grill.
If they misfire a lot, they will trigger "multiple misfire" 300.

I would move the coils and the sparkplugs from 3 and 4 to 1 and 2 (You could do just coils but since you have them out get the plugs as well).

Now, since the shop replaced all the sparkplugs, you should not have any problems taking them out (9/16 deep well sparkplug socket with extention).

https://www.amazon.com/OTC-6900-F-150-Spark-Socket/dp/B000NBVFN2


Drive the car and see if the errors changed to 301 and 302, if they did, then swap the coils back, and test it again, if the errors moved back to 303 and 304 then the coils are bad.
It's not unusual for new parts to be bad right out of package.
If nothing changed, then try swapping the injectors same way.
Inspect the little wires feeding the coils and injectors.
If that gets you nowhere, next step would be compression test.

For now, those are all my recommendations.

Maybe someone else will chime in.

Update: so I switched the plugs and coils and it went to cylinders 1 & 2. So I'm just gonna buy 2 new spark plugs and 2 new coils to see if that works....Is that the reason its has that rough idle and the hesitation?

 

[Explorer_PL]

Most likely.
What brand are all other coils ?
These engines will not throw a code unless it's severe. So you may have other cylinders misfire but not enough to show the 30x code.
But start with those 2.

 

[Sport Trac Mike L]

Most likely.
What brand are all other coils ?
These engines will not throw a code unless it's severe. So you may have other cylinders misfire but not enough to show the 30x code.
But start with those 2.

So I might as well replace all of em

 

[Explorer_PL]

That's what I do, once 1 or 2 misfire, I get the whole set. I keep the old good ones, throw away the bad ones and just keep them as spares for diagnostic purposes or just to get by next time.